• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.5
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• pp.468-482
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• 2016

To understand variations in the seawater quality of Asan Bay over four seasons form December 2011 to February 2013, we applied two methods: an in-situ observation of water quality and a comparison study of nutrient budgets among three parts (No. 1, 2, and 3) of Asan Bay. We found a significantly high nutrient concentration in the central part of the bay (No. 2) in July 2012 both in the mass balance study and in situ observation. We presumed the source of these nutrients to be both benthic effluence from old dam reservoirs and incompletely-treated municipal waste-water. This elevated nutrient concentration in the central part of Asan Bay (No. 2) expended to off-shore area and eventually triggered an intense Chl-a concentration in Asan Bay. Based on this result, we suggest improved waste-water quality control around the drainage area of Asan Bay.

• 전자공학회논문지 IE
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• v.49 no.1
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• pp.18-23
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• 2012

In this paper, a potable device application for DC-DC converter was designed for voltage protection circuit. Voltage protection circuit to offer the under voltage lock out and over voltage protection consists of a comparator and bais circuits were implemented using. XFAB 1um CMOS process, SPICE simulations was confirmed through the characteristics. Simulation results, under voltage lock out input voltage is 4.8 V higher when the turn-on and, 4.2 V less when turn-off. When the input voltage is low voltage is applied can be used to prevent malfunction of the circuit. Over voltage protection is 3.8 V reference voltage when the output voltage caused by blocking circuit prevents device destruction can be used to improve the stability and reliability. The virtual control circuits of the DC-DC converter connected. According to the results of the abnormal voltage, voltage protection circuit behavior was confirmed. The proposed voltage protection circuit of the DC-DC converter cell is useful are considered.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.11
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• pp.5897-5905
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• 2013

In spite of advantage by using BIM as quantity take-off, schedule control and clash check, absence of guidelines is a barrier to applying BIM to road domain. In this research, domestic and overseas cases of BIM guideline are analyzed in order to develop the road BIM deliverable submission system. The analysis is classified 5 topics which are BIM submit product list, submit files format, availability of existing 2D based products, BIM authoring tools and submit process. As a result, It needs a lot of effort to standardize BIM delivery system for road domain because BIM submit product list and BIM authoring tools are changable depending on BIM use cases. However, submit files format and submit process are common part to suggest guidelines of road BIM delivery system. It requires to combine BIM and 2D products for road BIM delivery system because delivery products are not exactly alternative 2D based delivery products for the present. The authors expect this research to use as basic data for development of the BIM deliverable submission system in road domain.

• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.246-249
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• 1994

Shelf-life of pork packaged under $CO_{2}$ was observed and the optimal volume of $CO_{2}$ gas was determined. High gas barrier film, EVOH($CO_{2}$ permiability; 1 $cc/cm^{2}{\cdot}24\;h{\cdot}atm$) was used as packaging material and the volume ratios of sample to $CO_{2}$ of 1 : 1, 1 : 3 and 1 : 5 were tried using the control of vacuum packaged pork. To ev.3luate quality of pork cuts, total plate counts, TBA, color and sensory score were monitored during the storage at $4{\pm}1^{\circ}C$ for 31 days. TPC of vacuum packaged pork increased up to $4.6{\times}10^{6}\;CFU/cm^{2}$ in 24 days while that of $CO_{2}$ gas packaged pork $4.5{\times}10^{5}\;CFU/cm^{2}$ at the same storage period, and it took 7 days more for gas packaged pork to reach the same TPC count. There was no significant difference in TBA value between vacuum packaged and gas packaged pork. In the color L and a values were not affected by treatment but vacuum packaged pork cuts showed higher b value than gas packaged pork. According to sensory evaluation, gas packaged pork showed less off flavor, better flavor and freshness than vacuum packaged one (P<0.05).

• Radiation Oncology Journal
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• v.21 no.2
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• pp.158-166
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• 2003

Purpose: To propose a conceptual design of a novel source for intensity modulated brachytherapy. Materials and Methods: The source design incorporates both radioactive and shielding materials (stainless steel or tungsten), to provide an asymmetric dose intensity in the azimuthal direction. The intensity modulated intravascular brachytherapy was performed by combining a series of dwell positions and times, distributed along the azimuthal coordinates. Two simple designs for the beta-emitting sources, with similar physical dimensions to a $^{90}Sr/Y$ Novoste Beat-Cath source, were considered in the dosimetric feasibility study. In the first design, the radioactive and materials each occupy half of the cylinder and in the second, the radioactive material occupies only a quater of the cylinder. The radial and azimuthal dose distributions around each source were calculated using the MCNP Monte Carlo code. Results: The preliminary hypothetical simulation and optimization results demonstrated the 87$\%$ difference between the maximum and minimum doses to the lumen wall, due to off-centering of the radiation source, could be reduced to less than 7$\%$ by optimizing the azimuthal dwell positions and times of the partially shielded intravascular brachytherapy sources. Conclusion: The novel brachytherapy source design, and conceptual source delivery system, proposed in this study show promising dosimetric characteristics for the realization of intensity modulated brachytherapy in intravascular treatment. Further development of this concept will center on building a delivery system that can precisely control the angular motion of a radiation source in a small-diameter catheter.

• Applied Microscopy
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• v.36 no.3
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• pp.227-234
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• 2006

To investigate the comparative effect of spherical and aspherical RGP lens were worn during 3 weeks on rabbit's cornea. Four white rabbits were worn right eyes with spherical lens and 4 white rabbits were worn right eyes with aspherical RGP lens. Left eyes were served as control. The rabbits were sacrificed at 3 weeks after fitting and observed morphological changes by scanning electron microscopy and also investigate proliferation rate of the corneal epithelium with RGP wearing. After spherical RGP lens wearing, the epithet layer damaged compared to aspherical lens. The superficial cell layer strip off seriously, cell size significantly changed abnormal. Both spherical and aspherical RGP lens fitting group showed so many bacteria and back surface of lens was found like a fern shape. The aspherical RGP lens original material type was some formal than spherical lens. We thought that these pattern was significantly altered with spherical lens by prohibited transmitter oxygen from atmosphere therefore the epithelium shape was changed. This suggested wearing the aspherical lens might be less physiologic than shperical lens fitting.

• Journal of Veterinary Clinics
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• v.30 no.3
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• pp.172-177
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• 2013

The aim of this study was to evaluate the in vivo and in vitro efficacy of enrofloxacin-silver sulfadiazine (Baytril$^{(R)}$ otic, Bayer, USA) for the treatment of otitis externa in dogs. Twenty-four dogs with otitis externa were included in this double-blinded, randomized study. The experimental group was treated with the Baytril$^{(R)}$ otic and the distilled water was applied to the control group. Both groups were administered each solution twice daily for 7 days and next 7 days off treatment. On days 0, 7 and 14, clinical signs, bacteriological and fungal counts were graded using semi-quantitative scales, respectively. For the evaluation of in vitro efficacy of Baytril$^{(R)}$ otic, we also performed Minimal Inhibitory Concentration (MIC) test by agar dilution method against Staphylococcus pseudintermedius, Pseudomonas aeruginosa and Malassezia pachydermatis. In the experimental group, the sum of clinical scores was decreased 81.0% and microbial scores were significantly reduced 87.0% at days 14, compared with day 0. The results of MIC testing were showed the concentration of enrofloxacin and silver sulfadiazine in Baytril$^{(R)}$ otic is high enough to kill for 3 infectious agents. No adverse reactions were observed in any of the dogs during this study. These results suggest that Baytril$^{(R)}$ otic are efficient and safe treatment for canine otitis externa.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.8
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• pp.1189-1196
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• 2014

This study investigated the effects of saltwort powder on the antioxidant activity and quality characteristics of patties added with saltwort powder. Patties were prepared with different amounts (0, 1, 2, and 3%) of saltwort powder. The total phenolic content, DPPH free radical scavenging activity, and pH of patties increased with increasing saltwort powder content (P<0.05). In particular, the moisture content and cooking loss of the group added with 2% saltwort powder were the highest and lowest, respectively (P<0.05). As the content of saltwort powder increased, $L^*$ and $a^*$ values decreased while $b^*$ value increased. Texture analysis showed that the hardness, chewiness, and gumminess of the control group were lower than those of the treated group (P<0.05). Consumer acceptability showed that 1% and 2% saltwort powder groups scored higher in terms of overall preference, appearance, color, taste, and texture compared to the other groups. Characteristic intensity rating of saltwort patties showed that as more saltwort powder was added, saltwort taste intensified; however, the increase did not affect juiciness, off flavor, or salty taste of the patties. Judging from the results, it was concluded that the addition of saltwort powder to patties in processing can enhance the preference, quality, and antioxidant activities of the patties, which elevates the value of patties.

• Fire Science and Engineering
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• v.23 no.6
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• pp.126-134
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• 2009

In an attempt to control the spalling in high strength concrete, spalling reducer was mixed to identify the effect and thermal characteristics of concrete beam member at high temperature. The member was manufactured in such as way of adding 40~60MPa of high strength concrete into spalling reducer, and then fire resistance performance were monitored under the ISO standard fire load condition in accordance with KS F 2257. As a result of test, fore rate performance of 40MPa beam without spalling reducer was 180minutes, 50MPa was 174minutes and 60MPa was 152minutes, indicating that 50MPa and 60MPa beam appeared 6~28minutes short to become a 3-hour rate. However, 50 and 60MPa beam mixed with spalling reducer appeared to have satisfied the requirements for 180minutes. A spalling was occurred in surface of 50 and 60MPa beam mixed without spalling reducer, while no spalling or surface failure was occurred with 50 and 60MPa beam mixed with spalling reducer. Thus polypropylene fiber mixed with the concrete proved to be effective, but viewing that the surface of 60MPa was peeled off partially, the steel fiber mixed appeared not to be effective for the beam more than 60MPa.

• Journal of Wetlands Research
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• v.21 no.1
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• pp.43-56
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• 2019

Irrigated and flooded rice paddy contributes to the greenhouse gas emissions (GHG) that affect climate. This in turn affects the supply and reliability of the water needed for rice production. This dynamic makes current rice production methods foreseeably less sustainable over time while having other undesirable effects. Intermittent irrigation by a means of the system of rice intensification (SRI) and alternate wetting and drying (AWD) methods was reviewed to reduce global warming potential (GWP) from 29% to 90% depending on site-specific characteristics from flooded rice paddy and analyzed to be a promising option for enhancing the productivity of water as well, an increasingly constraining resource. Additional benefits associated with the SRI/AWD can be less arsenic in the grain and less degradation of water quality in the run-off from rice paddies. Adoption and expansion of intermittent irrigation of SRI/AWD may require costly public and private investments in irrigation infrastructure that can precisely make irrigation control, and the involvement and upgrading of water management agencies and farmer organizations to enhance management capabilities. Private and public collaboration as a means of earning carbon credit under the clean-development mechanism (CDM) with SRI/AWD for industries to meet as a part of their GHG emission quota as well as a social contribution and publicity program could contribute to adopt intermittent irrigation and rural investment and development. Also, inclusion of SRI and AWD in programs designed under CDM and/or in official development assistance (ODA) projects could contribute to climate-change mitigation and help to achieve UN sustainable development goals (SDGs).